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Course: 8th grade   >   Unit 5

  • Angles in a triangle sum to 180° proof
  • Find angles in triangles
  • Isosceles & equilateral triangles problems
  • Find angles in isosceles triangles
  • Triangle exterior angle example
  • Worked example: Triangle angles (intersecting lines)
  • Worked example: Triangle angles (diagram)
  • Finding angle measures using triangles
  • Triangle angle challenge problem
  • Triangle angle challenge problem 2

Triangle angles review

Sum of interior angles in triangles.

109 ∘ + 23 ∘ + 48 ∘ = 180 ∘ ‍  

Finding a missing angle

x ∘ + 42 ∘ + 106 ∘ = 180 ∘ ‍  
x ∘ = 180 ∘ − 106 ∘ − 42 ∘ ‍   x = 32 ‍  
  • Your answer should be
  • an integer, like 6 ‍  
  • a simplified proper fraction, like 3 / 5 ‍  
  • a simplified improper fraction, like 7 / 4 ‍  
  • a mixed number, like 1   3 / 4 ‍  
  • an exact decimal, like 0.75 ‍  
  • a multiple of pi, like 12   pi ‍   or 2 / 3   pi ‍  

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Good Answer

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Triangle Interior Angles Worksheet and Answer Key

Students will practice solving problems involving the interior angles of a triangle .

Download this web page as a pdf with answer key

Example Questions

Directions: Use the Interior Angle Sum Theorem to solve each of the problems below

Picture Interior Angles of Triangle

Challenge Problems

Use your knowledge of the interior angles of a triangle as well as supplementary angles to solve the problems below:

Picture Interior Angles of Triangle

Visual Aids

Other details.

This is a 4 part worksheet:

  • Part I Model Problems
  • Part II Practice
  • Part III Challenge Problems
  • Part IV Answer Key
  • Interior Angles of a Triangle - Formula, Lesson and Practice Problems.
  • Interior Angle Sum Demonstration
  • Triangle Formulas

Triangle Calculator Interior Angles Demo

Ultimate Math Solver (Free) Free Algebra Solver ... type anything in there!

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COMMENTS

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  2. Solved Unit: Angle RelationshipsHomework 4NameDate -EXTERIOR ...

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  3. Math 8 Mrs. Volpe Unit 10 - Angles 2018-2019

    (4) Corresponding angles have the same measure. 4. Which statement is not true concerning angles A,B, and C in the diagram shown. (1) angle B and angle C are alternate exterior angles (2) angle A and angle C are vertical angles (3) angle A and angle B are alternate interior angles (4) angle B and angle C are corresponding angles 5.

  4. THANK YOU FOR YOUR PURCHASE! - MS. BATSON MIDDLE SCHOOL MATH ...

    7.G.2 Draw (freehand, with ruler and protractor, and with technology) geometric shapes with given conditions. Focus on constructing triangles from three measures of angles or sides, noticing when the conditions determine a unique triangle, more than one triangle, or no triangle.

  5. GeometryKeyUnit 5 - Relationships in Triangles

    AB 24. mZQSP CD mZQSR O Gina Wilson (All Things Algebra), 2014. Name: Date: Unit 5: Relationships in Triangles Homæork 7: Triangle Inequalities & Algebra ** This is a 2-page documenU ** Directions: If the sidæ of a triangle have the following lewths, find a rangeof Sible values for x. 1. PO=7x+ 13, 101-2, PR = x + 27 Range of Values: x + 40 ...

  6. Geometry: Homework Practice Workbook - 1st Edition ... - Quizlet

    Our resource for Geometry: Homework Practice Workbook includes answers to chapter exercises, as well as detailed information to walk you through the process step by step. With Expert Solutions for thousands of practice problems, you can take the guesswork out of studying and move forward with confidence. Find step-by-step solutions and answers ...

  7. learning focus

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  8. Angles of a triangle (review) | Geometry (article) | Khan Academy

    Since the sum of the interior angles in a triangle is always 180 ∘ , we can use an equation to find the measure of a missing angle. Example: Find the value of x in the triangle shown below. 106 ∘ x ∘ 42 ∘. We can use the following equation to represent the triangle: x ∘ + 42 ∘ + 106 ∘ = 180 ∘. The missing angle is 180 ∘ minus ...

  9. Solved Name Unit: Angles & Triangles Homework 1 Date Pd ...

    See Answer. Question: Name Unit: Angles & Triangles Homework 1 Date Pd COMPLEMENTARY AND SUPPLEMENTARY ANGLES In questions 1-3, use the 100 protractor below to answer the questions. Then, apply your understanding of angle relationships. 70 110 110 100 60 130 120 110 1. Determine the measure of each angle below. A meAFC= B meCFB- D m4EFC- meAFD= 2.

  10. Triangle Interior Angles Worksheet(pdf) and Answer Key ...

    Triangle Formulas. Triangle Calculator. Interior Angles Demo. Back to Triangles Worksheets Next to link 2. Free worksheet (pdf) and answer key on the interior angles of a triangle. Scaffolded questions that start relatively easy and end with some real challenges. Plus model problems explained step by step.